Form feeding mechanism for typewriters



Oct. 28, 1952 I A. H. SHARPE FORM FEEDING MECHANISM FOR TYPEWRITERS 5Sheets-Sheet 1 Filed June 19, 1948 INVENTOR.

A. H. sHARPE EORM FEFEDING MECHANISM FOR TYPEWRITERS Oct. 28, 1 952,

5 Sheets- -Sheet 2 Filed June 19, 1948 INVENTOR. ARTHUR h! S// RPEATTORNEY Oct. 28, 1952 A. H. SHARPE 2,615,550

FORM FEEDING MECHANISM FOR TYPEWRITERS Filea June 19, 1948 4 3Sheets-Sheet 5 BLANK PHONE CO.

JAMS" xxx xxx xx XXX XXX XX xxx xxx BLANK pnbus co.

DATE

f y p LA/J/L,

, INVENTOR. 4}? THUR H. SHARPE F" afm ATTORNEY Patented Oct. 28, 1952FORM FEEDING MECHANISM FOR TYPEWRITERS Arthur H. Sharpe, West Hartford,Conn., assignor to Underwood Corporation, New York, N. Y. a

corporation of Delaware I Application June 19,1948, Serial 34334 1 Thisinvention relates toltypewriting and other-frecord makin machines,.andmore particularly to mechanism for' quickly feeding work formsespeciallyof a continuous strip, into and out of typing position. The typing mayproceed, for a succession of forms, on the continuous strip conveyedpast the typewriter printing lineby means of a feed roll or platen,driven preferably by power for variable extents of paper feed. a

An object of this invention is to provide an efficient, preferablypower-drivenmechanism operableg after a form has been typed, to impartto a roll or typewriter platen a required rotag tion or, sweep ofcomparatively large extent so as to speedily bring the first typing lineof a succeedingform to the printing line.

Anotherobject is to provide such a mechanism for a. carriage-carried,revolvable roll orplaten t of a typing machine and efficiently in amanner so that the carriage mounting the platen may move in letter-spaceand return directions unimpaired -by the presence of such mechanism. Itis also an object of this invention to utilize efiicientlya motormounted in th e base of the typewriter as the source of power'for sorotating the carriage-carried paper-feed mechanism.

Anotherobject is to provide an eificient automatically operativeoverthrow prevention mechanism for the paper-feeding meanspsaidmechanism being transitorily operative at the end of each sweep feed ofthe roll or platen to prevent further rotation thereof, and beingautomatically restored to a normal ineffective position so as not tointerfere with ordinary rotation of the platen by the usual end knobsortheline-spacing mechanism.

- Asti further object is toprovideeflicient, re

liably operative means to havesuch form-feeding mechanism" operable onlywhen the paper carriage is in a predetermined, fully returned poi Qu-.,.

. It -is also an object to provide a manually operablerkey located inaconvenient position on the typewriter for effecting the form-feedingoperation. v

Another objective of the invention is to provide 'amechanism of theabove noted character which is simple in design, eflicient, and whichrequires a minimum amount of change in thecon-' struction of thetypewriter.

,Other objects, features, and advantages will be apparent from thefollowing description of apreferred embodiment ofv the invention.

In the drawings:

'11 Claims. (01.197-133) Figure 1 is a right sideview, partly insection,

of .a portion of a typewriter showing the invention applied-thereto, v

Figure 2 is atop view showing the typewriter platen and a portion of thebase frame with the carriage and. frame-carried sections of theform-feeding mechanism, i a v Figure 3 is a rear view of the right-handend of the typewriter showing. the driving parts and an interlockbetween the conventional carriage return'mechanism and the paper-feedingdevice;

Figure 4 shows the paper-feed drive clutch of Figure l at the time ofits release,

. Figure 5 is a view similar to Figure 4 .but showing theclutch at alater pointin its cycle;

Figure .6 is a front view, .partly in section, "or the form-feed.driveclutch and its connection to the carriage-carried drivev mechanism,

Figure 7 is a side view taken along the line I 1-1 of Figure 2 andshowing the-overthrow preventing means in the normal position,

Figure 8 is a view similar to Figure flout show-- ing the parts in theeffective position; I Figure 9 is an enlarged top view of a detentreleasing means shown in Figure 7, and f Figure 10 is an example of theformsusedin the machine of the present invention. a

, The invention is disclosed as embodied the well-known UnderwoodElectric Typewriter and therefore only so much of the typewriter as'isrequiredtoillustrate the application thereto of the mechanism of theinvention will be described herein. .7

' General description Themachine as described herein is designed fortyping the toll bills of the telephone companies. These toll bills aresupplied in theiorm of long strips with the appropriate headings printedat properly spaced intervals thereon, The strip is placed; in themachineby-passing it. from the rear under the platen andup in frontthereof. To the end of obtaining the, properpp-g erating condition ofthe form-feed mechanism,- the platen isfirst manually rotated inareversve; direction until it is arrested. Ihen'; the paper; strip isadjusted to position the first printingline on the leading form at theprinting point, and themachine is ready foruse, v n l V The dataidentifyingtheqpartywhose. bill is: being made out ,and the'date .are.first typed;- The carriage. is then returned rte-the: right :bydepression of the :usual carriage return? key :andi thefirsttoll chargeis typje'd-"outr The carriage is returned and the platen line spacedautofeed drive for the platen is driven from the.

splined shaft by way of a gear which partakes in the movements of thecarriage and which is slidable on the shaft and includes a gearconcentric with th platen shaft and carrying a springpressed pick-uppawl for the-platen. A lug on the platen is initially positioned incontact with this pawl by rotating the platen manually reversely. courseof typing each form, this lug movesaway from the pawl. this gear andpawl by the form-feed drive is thus idle until the pawl engages the lug,the form-feed mechanism being, constructed to turn the platen justsufficiently to advance the first typing line of the next form toprinting position. 'Afnovel'overthrow prevention device is provided' toengage a ratchet. wheel on" the platen at the endof each sweep feed,thereby to stop the platen from further rotation. The overthrow deviceis engaged" with such ratchet under control of't'he drive mechanism'butis released from it's engaging position only when it has checkedtherotation of the platen.

Although the platen sweep-feed mechanism is capable of advancing. theforms at any carriage position, it is'desirable that the forms'beadvanced only when'thecarriage is in its fully returned position and forthis reason, a form-feed clutch operating linkage is providedwithacarriage-controlled connection which renders an operationof' theform-feed key ineffective at any other carriage position. The form-feedmechanism and the carriage" return mechanism maynot operatesimultaneously since both will cause a feed of the platen. Anint'erlockto prevent such simultaneous operation of these two mechanisms hastherefore been provided. The combination of these two safety mechanismswill permit the platendrive to be' actuated only when the-carriagei's'in the -;fully returned" position and will permit the carriagereturn mechanism to beengaged with its'drive at any advanced point inthecarri'age movement only providing the formfeeding operation resultantfrom the prior depression of the form feed-initiating key has beenconcluded. I I I v Detailed description 7 The-typewriter to which thepresent invention is appl'iedi's, as has'been mentioned, thewell-knownThe initial rotation imparted to As the platen is line-spaced in the vUnderwood Electric and for that reason only so' much-of the structureas'cooperates with the new structure has been sho wn herein. The baseII, Figure 1, carriesaconstantly runningmotor I2 and 'a pair of'sideplates l3, only the right-hand plate-being shown herein. Mountedbetween the side plates I3 is a carriage guide rail ld on whichridesa'pape'r carriage-15; The carriage I5 is fed in letter-spacingdirection by a spring-driven drum I6 mounted between the si'd'e platesI3 and connected. to the carriage 15 by the usual flexible tape, notshown. Arack I'I on-the carriage I5 normally engages an:escapement-controlled pinion gear lBzto control. the letter space feedof the carriage l5. Thecarriage [5 may bereturned to its initialstarting position by a manually or carriage controlled return mechanismsimilar to that shown in the Helmond Patent No. 2,262,676, issuedNovember 11, 1941. The gear I9, clutch 20, bell crank 2I, link 22,clutch-operating lever 23 and shaft 24, Figure 3, correspond to elements112, 124., 127, 152, 153 and 113 of. said Helmond patent, and constitutethe clutch and clutch-engaging mechanism for the carriage return drive.Gear I9 is fixed to shaft 24 and engages a gear, not shown, driven bythe motor I2 so that shaft 24 is continuously driven during operation ofthe typewriter. A platen feed drive pulley 25 is fixed to the outer endof. shaft 24.

Platen feed mechanism A splined shaft 28 is journalled in the upper rearcorner of the right side plate I3 and in a bracket 29 fixed to thetabulator reed frame 30. see element '72 of the Helmond Patent No.2,262,676, noted above. Shaft 28 carries, outside cf plate I3; a'pulley3| which is freely rotatable on a reduced end'of shaft 28 and isretained thereon by a split washer 32, Figure 6, snapped into a groovein the end of shaft 28. A belt 33, kept taut by an idler roller 34,continuously transmits-a drive from pulley 25 to pulley 3I. The innerhub 35 of pulley 3| is toothed to form the drive element of a clutch forshaft 28.

Fixed to shaft 28 between the side plate I3 and pulley 31 is a disc 36provided with a notch 3'] anda clutch pawl 38, the pawl 38 being pivotedon the outer sideof disc 3 6 on a stud 39. Pawl 38 is formed with a lug-40 thereon to engage the toothed hub 35 of pulley 3'! and is tensionedfor movement into clutch-engaging position by a spring 4| connectedbetween the free end of pawl 38 and a stud 42* on disc 36. Pawl 38 isnormally retainedin its ineffective position by a bell crank 43 whichengages under a square stud 44 fixed to the free end of pawl 36 andprojecting through notch 31 in the disc 36. Bell crank 43 is pivoted ona stud 45 fixed in the side plate I3 and is manually operable undercontrol of a key 4, 46 in the typewriter keyboard to swing clear of thestud M, and thereby to institute asingle cycle ofsha'ft 28. Key 46 isfixed to-- a key lever' 4 which is-pivoted-on the usual key lever pivotrod 48 and is provided with a restorin spring 49. The rearward extensionof key lever 41 underlies a shoulder 58 of a vertical slide 5|, Figure3, mounted slidably'at its lower end by a stud 52, and further mountedslidablynear its upper end in an endwise enlarged 'slot in a bracket 53,both stud 52 and bracket '53 being secured'toa plate-54 fixed to a-bar55 between the'righ't and left-hand side plates I31" T-he upper end ofslide 5| is notched to provide a shoulder-56jwhich is normallypositioned under asquare stud 51 on an arm fifl pivoted to f'brac ket 54and extending through a slot SI in the right sideplate I 3;

- Pivot'edat' 62, Figures 1, 4 and 5, ompntera and resting on arm is anarm 63 carrying a pawl fi l pivoted thereon at Bil-and providedwith anupward extension E9. "A spring 66 connected between a stud' fil' onplate I3 and'a stud 68 on pawl it normally maintains arm '53 inoverlying relation against-arm 6i), and further maintains established bycontact of the stud 68 against the upper'edge of arm- 63 asshownin-Figure 1-. In

the normal position of 'paw-l 64', a square stud lIlthereon underliesidly arearward arm of"bell key 46,-- the bell crank 43 is displacedcounterclockwise by the' pi'n I9 andwill release clutch pawl- 38. Alatchleve'r 'I I also. pivoted on plate I3 on a 'stud 12,- has a tooth I3 onits lower arm and. further has "a bent-off ear I4 on the upper army-Aspring 15 between latch lever II and-bell crank 43 serves to normallymaintain theseparts in'thir Figure 1 position in which the tooth'liibears against the rear side of arm 69 and in which the bell crank 43 isretained in'clockwise moved position with its for'wardar-m in contactwith'a stud I6 on end plate I3. Disc 36 is. also provided with alpin TIon its inner side for cooperation with the. extended arm 69 of pawl 64.I "Qperatz' onp j platen feed clutch r The mechanism thus far describedis operative to" give a single cycle of rotation-to shaft 28 for eachoperation of key 46. Depressionof key 46' will rock bell crank 43counterclockwise by 'way of-slide 5I, -Figu're 3, arm 69, arm 63.Figure-l, and-st'ud -I9 of pawl 63.- Such rotation of bell crank 43releases clutch pawl39 which isthereupon pulled by spring-t engage thetooth 49 with the constantly rotating toothed hub 35 of pulley3 I.

tion latch tooth 13 under arm 69 which has'been raised by thedepressionbf key 46, thereby holdin'g' ar'm69,'arm 63, pawl 64 and bellcrank 43 in their actuated positions as shownin Figurel. Atapproximately 99} of rotation of pawl 38 and disc 36,- pin TI- on thedisc '38 engages the upwardly extending arm 69 of pawl 64 and, as shownin Figure 5, rocks the pawl- 64 clockwise about its pivot 65'tomove-square stud 19- from under bell crank 43'. Spring 15"thenrestores: crank 43 to its intercepting position, the return of pawl 64being blockedby the rear arm'of bell crank 43-so long as pawl 64 iselevated."

-Near the end" of the; revolution of disc 36 and shaft 2'8',--the stud 44 of clutch pawl 38"is inter cepted py'crank-ssand is moved radially ofdisc" 36' to"disenga'ge the tooth 40 of clutch-p'awl38 from the; toothedhub -35". During this radial movement, stud"44'enga'ges ear I4 of'leverH and moves it toward the front of, the machine to release tooth 13 fromarm 69 thus allowing restorationof' the key-operated parts 69-, .63 and64 to theirFigure lpo'sition, studlu of pawl 64 moving under,crank43'when armf63 moves back to normalposition. It will be seen-thatthe arm 69 remains operated from the startfto the end of the eye cPturnof the disc; This is so whether the, key 46 is immediately released ornot. As' will-become evident hereinafter so long as the arm69 remainsoperated, there can be no institutionof a; carriage return.

. Platea jeedmechanism rotation pr shaft 2 31 is transmitted to. a

pla n19 fixed to asleeve 1 9 rotatable in carriage I5fby a, train ofgearing carriedi'on the carriage I,"t he gearing including a gear8Iwhich is slid.

able: 1; but rotatable with shaft 28.

29" for sliding movementthereon. Hub 89 of gear 81- is als'o journalledinbearings 82"in a pair of.

carriage -carried frame plates 83 and 84. Plates 93"and 84. fixedlyspaced apart by screws 85 and spacers 96, by engagement with the facesof gear fl l-gc 'n'str'ain the -gear8I to move with the carriage-'1 I 5.7 A gear 89 1s journalled in bearings 82 Movement of 'pa'wl3B toits-engaging" position moves-square stud 44 from engagement with theback of ear- I4 of latch 1ever'I9whe'reupon spring rotates lever I9clockwise to posi 'b 'BD' of ear 18 I gure is "s' l n d t Shaft in theforward ends of plates 83 and 84 in a ma'nner similar to gear BI. Hub'99 of gear-89 isfreely rotatable on aplaten shaft 81; fixed in sleeve19; but is constrained against endwise" movement'thereon by the end ofsleeve 'l'9 and a collar'llflsecured to shaft 8'1. This gear- 89 isconnected to gear 8| by a pair of gears 9|, 92- rotatable respectivelyon studs 93 and 94,-tlie' studs'bei'ng fixed in plate 83 and passingthrough holes in plate 84.-

end of platen sleeve 19. A collar 96, formed with a single tooth 91, isfixed to'the extended-portion of hub 99 by means of a'set screw 95. r

A ratchet gear 98 issecured to the right end of sleeve 19 and carries apawl I99, Figures 7 and 8, with a tooth I9I. Pawl l99 is pivoted on theright side of ratchet gear 99- and is urged inwardly by a spring I94into engagement-with the collar 96 and tooth- 91. Fixed to theleftend ofplaten shaft 8'! is a line-space ratchet wheel I92 which'isdriven stepby step in the usual man; ner to fe'ed the paper past the printing-lineof the type.

Side plate 84 is held against sidewise movem'eri't' o'n hub-99 by collar96 and the left side of-gear 89 and plate 93 is similarly held byitsconnet'iftion' to plate 84. Referring to Figure'S, it may be seenthat the rear-end ofthe frameis likewise con-' strained to'movewitlifthecarriage by'a plate '99- secured to a bar I93 on carriage I5the frame plates 83 and 84'. 4 I

lnoperation, the platen shaft 81 W111 be age one or more lin'e spaces asthe typing progresses so'that pawl I99 fixed tothe shaft will-rotateahead while the tooth 97 remainsfstationary. Upon depressionofsweep-feed key 46', the shaft 23 will, as previously set out be' driven'one'com-Q pletef revolution This rotation will be transmitted'from-shaft28 by'gear SI splined thereon,

through gears 92-, 9|, and '69 tohub 99 and fto": tooth 9'I'on collar96. I he extent'of rotation of sleeve 99 and tooth 91 is-constant forevery turn given the shaft 28, and in the embodiment of the inventionshown, equals one turn plus an equivalent ,of .a specific number. ofline spaces. Obviously; thesizes of gears BI "and 89 are selectedimaiccor'd with the length of the particular form'- to-be used, and,unless. the length of the formis exactly equivalent to thecircumferenceof' the platen, the latter-will at-the endof each :rorm: feedingoperationiassume a' difierent rotative position. After an idl period ofrotation 'ofi sleeve .99, as determined by therotative move ments'impartedito the platen shaft 81 through? line-spacing action,- thetooth 91' will engage and pick up .the' tooth I 9I of pawl I99; Furtherrota tion of the gear99 and tooth 91 will cause rota tion of platenshaft 81 by an amount whichin reference tofthe form length iscomplementary to. the; extentv of rotation given shaft- 81; P during thetyping operation. The additional rotation so given toiplaten IB-Qn eachcycle of shaft 29', f willibe appropriateto advanc'ethe strip of formsto the first typing line-of the next form irrespec-'- tive of the extentof previous amount of move ment given the platen by line-spacing em'ovements. v I '1 The platencnd bill chute The forms used in the disclosedembodiment I are, as shown in Figure 10, printed on a long stripofpaper. I96 which is perforated as at I91 for easy separation of theforms,

e The left-hand end of hub-99 is extended to pass through plate 84 toabut the and embracing I The strip I usually folded along lines I91 intoa mamrom" 1" packfor: convenient handling. The-strip I06 is: guidedabout platen I8 by a. chute comprising,

members I08 and I09; Figure 2, having identical of bail H2 andis-therefore made lengthwise a'd iustable-to provide'new bearing areasfor the-bail I I2. The rod H3 is adjustably held against endwisemovement by upturned ears H4 of a; pair of. stops H5 secured by screwsH6 and I IT to brackets H I. Screws H6 pass through slots H8 inistopsII5 and when loosened will free stops I I5- for adjustment of cars II4about screws H'l. Chute guides I08 and I09 carry set screw collars IVI9-by. which the guides: may be. fastened to rod H3 to prevent distortionof the forward end. of theguides.

ltl-will-be notedthat the platen I8 has been reduced in length to lessthan one-half of the usual. size. More length is not needed. sincethe-stripl06 isnarrow and is advantageous since the elimination oftheexcess length. both reduces the force required to prevent overthrow ofthe platen feed mechanism and allows room for the feed mechanism insideof the. carriage and plates, thereby simplifying the constructionand-assembly. Knobs I20 are fixed to the outer ends of platen shaft 81to allow a manual line spacing. of the platen I8 in either direction;Due, however, to the pawl I00'on ratchet 98 and tooth 91' on. collar 96,theplaten may not be reversely rotated past the first typing line of theform being typed on but may be rotated forwardly without interferencesince pawl I00 will freely rideover tooth 91in thisidirection.

Qverthmw' prevention mechanism A- novelmechanismhas been provided topreventan excess rotation of the platen I8 th'rough momentum at the end ofits sweep feed. This structure is: normally ineifective and isthrowninto its active position only at the endcf' a. form-.- feeding cycle.Restoration of the overthrow preventing meansto idle condition iseifected under controli'of theplaten as the latter is arrested.

and-.overerotationcf the platen. is prevented. The platen in itsconcluding movement, .by' powenof" momentum stored therein, acts on. andremoves the? overthrow-preventing means: from interference with furtherplaten rotation. This preventingmeans as. shown in Figures- '7 and 8 isauxiliary stop slide' I25 with slots I28 is slidably mounted on a pairof studs I2! on lever I23 and:

is urged to aforward position by a spring I29 connected between the twolovers" I23 and I26. In thev forward position of slide I26, Figures, itsstop nose I30? is slightlhahead oijthe correthe slide. in: its rearward.positionon the. lever,

I23 and; so as toallow the lever I23 to occupyits-normali position clearof the ratchet wheel- 9.8;, Responsive-to: the operati'onof thekey46,;theishaft 28 rotates clockwise;., andathus the'-ear-I-33 moves away;from: the: projection I34 to: permit spring; I29? tor move: slide I26 toits forwarcrnositi'on onthe lever. I23. Near the endfof' the full.-cycle: of rotation of shaft. 28,. see. Figure- 8, ..the; ear I33 moves:under: projection: I34 to raise-the: rear end of slide I26 and lever I23and thereby to depressthestop noses I30; I 3I of the lever and slide:into the path of one of the teeth of the ratchetwheel 98. Theclutchpawl=: isforcedi free: of theotoothed-hub 35before the full revo-rlution. of the shaft 28 is completed, 'butsuch.-

shaft completes its revolution byrstoredimom'en-n tum. Furthermore, duet theacquired inertia'of. the platen 18,. the ratchet wheel 98;andtheplaten; knobs I 20,. these partsdo notstop their counter clockwiserotation when the drive-from the tooth-.- 91- ceases. During thecontinued rotation f platen I8, a tooth of. ratchet wheel 98 advances.intoengagement with the projectednose I30 ofi s1ide: I25- and forces theslide; rearwardly to av position wherein it may dropandbelatch'ed beehind ear' I33, Meanwhile, however, the advanc ing tooth of theratchetwheel 98engae'es'thet nose of the lever I23 to prevent further. advance:rotation of the platen: Since" the. pivot of lever. I 23, namely thestud 94, is1slightly outsidea liner tangent to the wheel 98. at apointofcontaot; withnose I30, the lever I23will not immediatelv." moveireezof thera-tchet wheel 98 when the 02:11]? ming: projection I3 4-moves rearwardly of; theiear. I33, but will temporarily cling to theengaged; wheel tooth. Uponthe clash of the. wheelitooth with thestop=nose- I3I'; there-ensues a slightlree bound of the-wheel andplaten, and the spring I25 is resultingly enabled to swing. the lever I23 with the. slide I26 soas to position the stop noses: I30, -I3I clearof theratchet wheel 98. Thusth m stop nose I3I, comprising,thE-MJVGlYthEOW-DIB-i venting means has been transitorily; active.

Flatten detent release A1 platen vdetent I 31', Figures I 7. and 9,carrying. a. roller. I382 is pivotedronstud-93 andtensioned by a.sprihg- I391 connected. theret ntosengag e roller. I 3 8. with. theteeth. of ratchet 98 and. thus hold"; the platen; 'I'B inits adjusted.line space po- '7 sitions The detent. roller. I38 islocatedsothat thewheelilt upon arrest. by the nose I3l will; come to rest in a slight.back-up relation. with.

respect to the stopping nose- 'If3IQ. as is. clearly evident from Figure7'. 'Duringa. sweep fedof the platen I8 to advance strip I06 to the nextform, it is desirable to release? roller I 38 from ratchet 98. CollarI32 is formed with. acam notch I40' so positioned that in thenormaI.po-.

..si'tion,o'f shaft 281.21g. roller. I II.onafplateJIH? may enter.into-thenotch' I40.. Plate- I42 ispiv oted on stud 94" and tensionediclockwise by a spring I43 connected). to. its upper end. and-aconvenient part of. frame. plate. 84." AT screw:

. I44 is adjustably 'fixed in anear. I45'of plate-J I 42. and cooperateswith. a. corresponding bent-I eari I46 ondetent lever I3I'..'. ColIar.I.32,.duri ng the. initial. part of therctation of shaft 28,-rocks.

plate I42 countercloc'lrwise and this. movement} ofi plate. I42 istransmitted through screw I to detentlever I31 thus moving roller I38 tothe dotted line position of Figure 7 where it is out of'engagement withratchet 98. Atthe end of the revolution of shaft 28, roller I38 againdrops into notch I40 and frees detent lever I3'I for movement into itseffective position.

' V DisdbZin g of form feed mechanism 'To. insure that a new form willbe properly positioned for. immediate typing, the effectiveness of thelinkage from key 46, Figure 1, to clutch release pawl 64 is placed undercontrol of carriage I so'thata form-feed cyclecan be initiated only inthe fullyreturned position of the carriage. Referring to Figure 3, itmay be seen that the upper end of slide 5| is urged to the rightend ofthe slot in bracket 53 by, a spring I50 con-v nected between a stud I5Ion bracket 54 and a lever I52 pivoted on a stud I53 of slide 5|.Another-Istud I54 on slide 5| is engaged by the lower end of lever I52to prevent clockwise rotation of lever I52 from its Figure 3 position.In the righthand position of slide 5|, shoulder 56 is not under stud 51of arm 60 and vertical reciprocation of the slide 5| by key 46 is thusineffective to initiate a form-feeding cycle. Slide 5| is moved toitseffective left-hand position by a tappet I on the carriage l5 whichwill, in the extreme right hand'position of carriage I5, to the leftFigure 3, engage an ear I56bent oil? of lever I52 and move shoulder 56to the effective posi tion under stud 51. It may, however, happen thatthe form-feed key 46 will be depressed before the carriage has movedinto its extreme right-hand position in which case slide 5| cannot.,moveto the left'in Figure 3 since stud 51 willflengage the side of slide 5|..In such case,

. contact of tappet I55 with ear I56 will rock lever I52j'idly, aboutits pivot stud I53. Uponrelease of keyj46, slide 5| is restored to itslower positionby spring I51 whereupon spring I50 will move slide 5|tothe. effective position under stud I51. The key 46, if thenreoperated, will insti-' 'tute a form-feeding operation.

Carriage return-form feed interlock Aninterlock is provided between thecarriage return controls and the form-feed controls to .prevent' theirconcurrent operation and possible and thefgear hub 86, a simultaneousoperation, of these twomechanism's might cause damagethrough .stallingof the machine due to excessive friction at'the spline fit between thehub 80 and the shaft 28. To prevent-such simultaneous operation, anarmIGOQFigure 3, with an earIBI ben't from it is mounted on the carriagereturn initiating lever 23. A plate I62 is fixed to the form-feed armand will, in the operated position'of arm 60, lie over ear I6I' andprevent movement of arm 23 for engagement of the carriage return clutch20. It will be remembered that the arm. 60 is moved to operatedpositionby operation of the key 46, and is held thereat by the latch lever IIuntil theend of the cyclic turnof the shaft 28, at which time by theoutward displacement of the pin 44 of the clutch ure 3 and'the .ear-I6Iof sucharm will then'zliein .the'. operating path of the 'plate- I621and .rwill prevent movement. of :the arm 6I| 1301 aclutch-- closingposition for form=fe ed. 1: -J;

The embodiment di'sclosedis :not-the only form which is within'the scopeof: the present .invene tion as various modifications and changestmaybe'made without departing from the invention as set outinthe appendedclaimsm'v 1v Whati-sclaimed I 1. In a typewriter having-'a'frame, anda'car' riage slidablerthereom the combination" of a platen shaftrotatable insaidcarriageya platen onsaid shaft, a-imotor, andmoter-operated means to rotate said: platen to a predetermined point,said means comprising ashaft supportedon said frame, means'rotatableonsaid platen 'shaft'ya member on said platen shaft engageable bysaidrotatable:means. in one-direction :of' rotation thereof,-carriage-carried means slidableon and rotatable with saidframe-supportedshaft, means on said. carriage operativelyconnecting said slide ablemeans andsaid rotatable, means,akey.;con-. trolled means driven by-saidmotor .to give .said shaft singlecycles of rotation, and means operateed by said slidable means at the end of 'a rev'olue tion of saidframe-supported shaft. to stop rotation of said platen shaft.

2. In a typewriting machine; a frame; aiJcar riage movable thereon, aplaten rotatableinsaid carriage, azdriving, member concentric; with saidplaten, a'ilQstiTmotion, one-way;., connection;;- between: said:-platen. and :said; -member; a :shaft on said framepa carriage-carried,gear.pslidable on said shaft; and splined thereto, gearing con: nectingsaid slidablegear andsaid driving mem-. bei', .keycontrolledmeansforrotating said shaft; and meansfto. preventexcessrotation ofisai'd platen; saidumeans comprisingxa ratchet-,vvheel" fixedtosaid platen,-a stop lever on saidacarllage,

a'sto'p :slide on said lever and-ai-cam ongsaid slidable :gear, :saidcam co--acting :with said i-stop slide to depress saidlever and slideinto {blocking engagement, with said ratchet Wheel whereupon excessrotation of saidplaten;movespsaidslide to a position free ofsaid cam;-11

3. In-atypewriter havingga frame, a'carriage movable thereon, a platenin saidcarriaget and: a

source ofpower; means'ato rotate said platen to an advanced positioncomprising; a shaft, driving means between! said shaft and said platen;said driving meanshavinga lost motionone-wfHhdriYe to said platen,;aclutch dog-onsaidshaft -a power drivenmember freely rotatable-on-saidshaft,

said drivingmeans having ,a lostmotion ones-way drive to said platen, aclutch dog on saidshaft, a

power driven member freely rotatabley oir said, shaft, members torelease said dog to permit-itv 11 tolengage said :power. driven-memberand "to disengagesaiddog at the end :of one revolution 'ofsaid shaft, a1key-operated slide toioperate said release members, :means' normally:hol'ding :said

;slid"e:;in .an inefiective position, means on "said carriage tomove-said slide to an efiective position, a cam operated by said. shaft,means :set by said card at the end of -a revolutionthereof to stoprotation of said platen, and meansresponsivetto-the arrestyof the platenby said cam-set means for resetting said cameset means to an ineffectiveposition.

5. *In-am'achine of the classldescribe'd, having a paper-supportingcarriagemova'ble on-a frame; a paper-feeding roll supported on :saidcarriage to v.turn on .an axis extending parallel -to the direction ofcarriage movement; means movable alongwith ,the carriage and operable toimpart rotative movements to said-roll .which place the latter indifierent-rotative positions, said rotation imparting means-including arotatable :elementshavingan axis extending parallel to :the carriage,power-meansto 'imparta single rotationtosai'delement, comprising aone-revolution clutch on :the frame axially in alignment with said:element, :and I means :including shaft means extending parallel to thedirectionlo'f carriage movement; connecting said vclutch operativelywith said element in any position of the carriage, a circular-arrayof-teeth associatedrfor rotation instep with said roll, and means on thecarriage, responsive'to said element at the end of each revolutionimparted thereto, to .move :into rotation limiting relation with saidteeth, thereby to stop rotation-ofsaid-roll. I

6. In a machine of the :class described, having apapen-supportingcarriage movable on a frame; a paper-feeding rollsupported to turn on said carriage means movable along with the carriageand operable to'impart rotative movements :to said roll which placethe'latterin different rotative positions, said rotation imparting meansin cluding an :element having an axis extending parallelto the carriage,powerr-meansto impart asingle revolution to said element, comprising,acne-revolution clutch on the frameaxially in alignment with saidelement, and means including splined shaft means extending parallel tothe direction of carriage movement, connecting said clutch operativelywith said element in any position of the carriage, means on thecarriage,

, responsive to said element at the end of .each

revolution'imparted thereto, to stop rotation of saidroll,'a"-key-control on the frame operable "to close said clutch for onerevolution of said shaft means, "and means including a control elementon the carriage to incapacitate said key-control in all but a returnedposition of the carriage;

-'7. In a machineof the class described, having aQpaper-fee ding roll, awheel associated with said roll and having teeth gforming notchesdefining linees'pa ce positions, a line-space detentnormallyiniengaglement with .anywheel notch, means oper able to impart,extensive rotative movements to said roll which place said roll indifferent linespace positions, an elementwhich is given asinglerevolution each time said operable means is t impart .a rotativemovementto said roll, means normally clear of said detent wheel and-transitorilyresponsive to said element atxthe end of each revolution to move intorotation limiting engagementswith the teeth of said whe'ehand meansincluding'control means .on said element, to release said detent at theoutset of each revolution "ofzsaid element and to apply in; again when:th'e revolution nears conclusion.

8."In:a machine of the classdescribed having a paper feeding roll :and--a turning member ffor saidroll, means al-ways :rot-arily connectedwith said roll and comprising'tee'th arranged in =a circular array anddefining aseries of different rotative positionsfor said roll, a singlerevolution element, power means to impart singl revolutionsto saidelement, motion :transmittingmeans always ready to transmit motion fromsaid element to said :member and at a ratio iforsaid element; at :eachrevolution thereof to drive the roll :to one-of :the said ro tative:positions defined :by said teeth, a deviceconditionable'iorr01lstopping ooaction with any one of said teetharriving at a certain position at the end-o'f eaoh revolutionof saidelement, means on-sai'd element and in control oversaid device tocondition the latter atthe conclusion of each revolution of saidelement, and means responsive to the ensuing roll-stopping coactionofsaid devicewi'th one of said teeth to placesaid. device automatically*in ineffective condition permittin impartation of a new revolution tosaid element.

-"9. In amachine of the class describedhaving a paper-feeding roll and;a turning member for said roll, :means constantly connected to -saidmember and operable to impart rotative movements thereto whichwill-place-suchroll in any one of a number of evenly spaced :rotativepositions, said operable means including an element which is given asingle revolution-for imparting each of said rotative-movements to saidroll, a circular array of teeth associated with said roll for rotationconcentrically -therewith, said teeth circularly spacedin conformancewith the rotative ,positions of .the roll, and mean responsive to saidelementnear the conclusion of each revo lution thereof to move into thepath of 'saidrteeth for roll-stopping coaction .Withone of said teeth;and-responsive to said, roll-stopping ,coaction with any of said teethto move automatically ,clearof the path of said teeth and permitimpartation of a new rotation to said element.

10. In a machine of the class described, having a carriage movable on aframe and having'a paper-feeding roll mounted on the carriage to turn ona certainaxis, means to power-rotate said roll, comprising,ashaftrotatably mounted on the frame and'extending parallel to the.carriage, on anlaxis different from that of said roll. anelementturnable'by said shaft andihaving ,a splined connection therewith formovement along said shaft, means on the carriag to cause said l m nt tomove alon with the carria e, ,means to transmit rotary motionirom .saidelement to said roll, and power means to impart single rotations to saidshaft, meansalways rotarily .connected with said roll and comprising atooth moved toward :a certain location each timeisaid element approachesthe end of a rotation, a device ,conditionable for roll-stopping.coaction with said tooth. means on said element in control over saiddevice to condition it at the conclusion-of each rotation of saidelement for roll-stopping .coaction with said tooth, and meansresponsive to the ensuingroll-stopping coaction of'said device with saidtooth to place said device automatically :in ineffective condition topermit im partation of anew rotation to said. element.

.11. In a machine of the class described having a paper-feeding roll, arotary element, power means to impart single rotations to said element,

gear means to transmit rotary movement from said element to said roll, aline space detent wheel associated with said roll and provided withdetent notches, a detent normally engaged with said wheel in one of itsnotches, and means to release said detent during each rotation of saidelement, comprising, a cam unitary with said element, and meansincluding a follower controlled by said cam and operatively connectedwith said detent to release the latter at the beginning of each singlerotation of said element and to apply it again automatically at the endof the same rotation.

- ARTHUR H. SHARPE.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,113,103 Cooper Oct. 6, 19141,133,004: Carlin Mar. 23, 1915 2,066,305 Carroll et a1 Dec. 29, 19362,251,147 Mann July 29, 1941

